Soil Amendment Calculator
Calculate how much lime, sulfur, gypsum, or compost to add to your soil. Enter area and application rate for bags and volume needed.
๐งช Soil Amendment Calculator
Results
Area100.00 sq ft
Total Amount5.0 lbs
40 lb Bags1 bags
50 lb Bags1 bags
๐ก How to Calculate Soil Amendments
Soil amendments are applied at specific rates per 100 square feet, depending on the material and your soil test results. Agricultural lime is applied at 3โ8 lbs per 100 sq ft, elemental sulfur at 0.5โ2 lbs, and gypsum at 3โ5 lbs. Compost amendments are measured in cubic feet.
Always start with a soil test to determine your soil's current pH and nutrient levels. Lime raises pH (makes soil less acidic), sulfur lowers pH (makes soil more acidic), gypsum improves clay soil structure without changing pH, and compost improves overall soil health and water retention.
A 10ร10 ft garden bed needing lime at 5 lbs per 100 sq ft: area = 100 sq ft, total lime = 5 lbs. For a 50ร50 ft lawn at the same rate: 2,500 sq ft ร 5/100 = 125 lbs = about 3 bags of 40 lb lime.